IBM announced on Aug. 23 that it is acquiring Internet Security Systems, a maker of network security and appliances, for $1.3 billion, or $28 per share.

The purchase of ISS, the fifth largest in IBM's history, is the fourth acquisition for Big Blue since the start of August. In less than four weeks, the Armonk, N.Y., company has purchased three other software companies—Webify, MRO Software and FileNet.

In its announcement, IBM officials said that ISS, which specializes in intrusion detection and other system-scanning technology, will add to the company's remote monitoring and security mangement portfolio.

Following the completion of the acquisition, which is subject to regulatory conditions, ISS will be folded into IBM's Global Services Security organization.

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"ISS is a strategic and valuable addition to IBM's portfolio of technology and services," Val Rahmani, general manager of infrastructure management services at IBM Global Services, said in a statement.

"This acquisition will help IBM to provide companies with access to trained experts and leading-edge processes and technology to evaluate and protect against threats and enforce security policies," Rahmani added.

The latest purchase by IBM is another example of well-established, blue-chip IT companies snatching up sizable security software makers as a way to expand their presence in the security space and add technology that helps expand existing product lines.

Another example of this trend happened in March, when storage giant EMC bought Authentica.

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The acquisition of Atlanta-based ISS will give IBM an automated security platform. The company then hopes to offer standardized, enterprisewide pre-emptive protection against security threats.

IBM plans to integrate ISS' software with Tivoli's IT services management portfolio, which will also include software for identity management, access management, SOA (service-oriented architecture) and security information management.

IBM will also use the acquisition to enhance the capabilities of its business and IT asset management consulting practices.

The latest acquisition comes at a time when companies such as IBM and EMC are looking to stay competitive against Microsoft as the software giant expands its own security portfolio.

In addition, IBM will use ISS X-Force security intelligence services, which protect networks with analyses of online vulnerability, and add the company's security operations centers to its own global network.

ISS was recently contracted by the U.S. Department of Veterans Affairs after the federal agency announced a massive security breach after a laptop was stolen from an employee's home.

Editor's Note: Senior Writer Matt Hines provided additional reporting for this story.

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